Microbewerking met behulp van lasers

Het bewerken van materialen met behulp van lasers staat momenteel enorm in de belangstelling, en terecht. De ontwikkeling van bestaande en nieuwe typen lasers staat alles behalve stil. Ontwikkelingen bevinden zich met name in het gebied van hogere vermogens, betere bundelkwaliteit en hogere bewerkingsnauwkeurigheden. In dit artikel wordt ingegaan op de microbewerkingen die realiseerbaar zijn met behulp van lasers

Probiotics: immunomodulation and evaluation of safety and efficacy.

The intake of probiotics has been associated with beneficial effects on the immune system, such as improved disease resistance and diminished risk of allergies. This review gives an overview of the immunomodulatory effects of probiotics investigated with in vitro assays, experimental animal models, and clinical trials, and explores possible mechanisms underlying the immunomodulatory effects. Immunomodulation, however, is not always beneficial and might induce detrimental effects; therefore, a scheme is proposed for benefit-risk assessment of immunomodulation by probiotics. Within this scheme, expert judgment based on data derived from a panel of in vitro assays, animal models, and clinical trials should lead to conclusions on efficacy and safety aspects of probiotics

Personality, health behaviors and quality of life among colorectal cancer survivors:Results from the PROFILES registry

Contains fulltext : 170340.pdf (Publisher’s version ) (Open Access)PURPOSE: There is a paucity of research looking into the relationship between personality and health behaviors among cancer survivors. The aim of this study was to investigate whether Type D personality and its two constituent components, negative affectivity (NA) and social inhibition (SI), are associated with health behaviors, quality of life (QoL), and mental distress among colorectal cancer (CRC) survivors. METHODS: A population-based study was conducted among 2,620 CRC patients diagnosed between 2000 and 2009, who completed measures of personality (DS14), health behaviors, QoL (EORTC QLQ-C30), and mental distress (hospital anxiety and depression scale). RESULTS: Personality was not associated with body mass index or smoking. Those scoring high on NA (with or without SI) were more often nondrinkers and less physically active compared to those scoring high on neither or only SI. Personality (high scores NA) and health behaviors (inactivity) were independently associated with poor QoL and mental distress. CONCLUSIONS: CRC survivors with high scores on NA are at risk of being inactive and have worse health outcomes

Mechanisms of Hexachlorobenzene-induced Adverse Immune Effects

Hexachlorobenzene (HCB) is an environmental pollutant that can induce adverse immune effects in humans and rats. Brown Norway rats (BN) appeared to be very susceptible to HCB-induced immune effects. Oral exposure causes inflammatory skin and lung lesions, enlarged spleen and lymph nodes (LN) and elevated humoral responses. Although the immunopathological effects induced by HCB are investigated comprehensively, the exact mechanisms involved are unknown. Experiments described in this thesis were performed to obtain more insight in the mechanisms underlying HCB-induced adverse immune effects, both on a cellular and molecular level. The immunomodulatory effects of the oxidative metabolites tetrachlorohydroquinone (TCHQ) and tetrachlorobenzoquinone (TCBQ) were assessed. Therefore, these metabolites were studied in the mouse reporter antigen popliteal lymph node assay (RA-PLNA) with TNP-Ficoll as a RA. In this assay an isotype switch to IgG1 indicates that the chemical injected is able to form neoantigens that can stimulate T cells. Both TCHQ and TCBQ induced an isotype switch to IgG1 and were thus capable of providing neoantigen-specific T cell help. Furthermore, this response was compound-specific as was shown in a secondary PLNA. In addition, gene expression profiles with DNA microarray analysis in BN rats were obtained. Transcriptome profiling was done in spleen, mesenteric lymph node (MLN), thymus, blood, liver and kidney. Data confirmed known effects of HCB such as stimulatory effects on the immune system and induction of enzymes involved in drug metabolism, porphyria and the reproductive system. New findings include the upregulation of genes encoding pro-inflammatory cytokines, antioxidants, acute phase proteins, mast cell markers, complement, chemokines, and cell adhesion molecules. In general, gene expression data provide evidence that HCB induces a systemic inflammatory response, accompanied by oxidative stress and an acute phase response. The role of T cells in HCB-induced immunotoxic effects was investigated further by using the Cyclosporin A (CsA). This immunosuppressive drug decreases peripheral T cell numbers and inhibit T cell activation. CsA treatment delayed the development of HCB-induced skin lesions and prevented the increase in spleen weight slightly. Furthermore, increase in ALN weight, lung eosinophilia and humoral responses were prevented completely by in HCB-exposed rats treated with CsA. Macrophage infiltration was independent of T cells and macrophages seem also important. Therefore, the relationship between macrophages and T cells was further investigated. Co-administration of clodronate-liposomes was used to eliminate macrophages in HCB-exposed rats. Results indicated that macrophages played an important role in HCB-induced skin lesions, in particular in the aggravation of skin lesions. Also, HCB-induced lung eosinophilia and elevation of anti-ssDNA IgM antibodies were less pronounced after depletion of macrophages. To obtain information on events that occur in the initiation phase a kinetic study was performed. This revealed that both skin and lung pathology were early inflammatory events. Furthermore, macrophage infiltrations in the spleen seemed to precede the increase in spleen weight. Remarkably, studies performed to further assess the functional role and specificity of T cells induced by HCB did not provide any evidence for the presence of T cells specific for TCBQ. Moreover, HCB-induced immune effects could not be adoptively transferred to naive recipients